Test Equipment Anonymous (TEA) group therapy thread

[mansaxel]

Aieeee... commiserations... I think we've all been there, or thereabouts.

I still have a PM3218 in the repair queue that has a jigsaw puzzle for a display bezel, and a control panel whose concavity is definitely not in the original design...   

My Marconi VTVM came in more or less a plastic bag with some padding, courtesy of GSP, UK division. But it works and is reasonably in spec too.

[tggzzz]

      

   You can't even tell that there's ringing with either sample. What all you've done here is to prove that a 40-year-old scope still has value. 

mnem
 

That Siglent only has a 50MHz B/W. I would cut it SOME slack.

I wouldn't 

Why not? Just cuz it's med...? 

In all honesty... that signal on med's 2465 is a gorgeous example. Brings a tear to my eye; knowing this generation will never know the joy of actually SEEING the signal, even through a "microscope lens", as opposed to seeing a transcript of what a computer subroutine THINKS it sees and extrapolates from datapoints.

mnem
 

Turn off interpolation, and look at the unconnected dots. Then you can see what you can't see.

Being able to figure out what you can't see is not the same as being able to see it. Those dots are the same kind of lie as the statistics on any kind of chart used by any politician to sell whatever big lie they're pushing at the moment.

In what way are they a lie? You may misinterpret them, but that is a different problem.

[tggzzz]

Those dots are the same kind of lie as .............

Nope, they're what interpolation waveform reconstruction is based on, however any scope with a small memory depth will have lesser dots for interpolation to work with.
Yet it's always the operators understanding that allows settings to be made so to minimise interpolation errors.

Repetitive waveforms aren't usually a problem but fast edges and non-repetitive waveforms are.

-----------------------------------------------------
tautech
totally dotty !

A collection of datapoints is just that; it is NOT reality, but rather an approximation thereof.  You don’t know what you’re NOT seeing in the spaces between those datapoints; all you have is the computer’s best guess. As med’s example makes abundantly obvious, in some cases that guess is pure shite.

Neither is an analogue trace reality; it is only an approximation thereof. Start by considering the effects of the probes on the circuit, then move onto frequency and (especially) phase distortions.

(Geocities font omitted for legibility )

[McBryce]

Hello, my name is BreakingOhmsLaw and i suffer from GAS.
Today if have something for you, that probably is new even to this forum.

I present to you *drumroll* the Citizen CQT-101-C Quartz tester.
What is it? Well, basically its a frequency counter for wrist watches. It comes with a little pedestal for you to place a wrist watch on. Theres a hypersensitive microphone inside that listens for the watch ticking.
The ticks are measured with high precision, and the device shows the deviation of the watch in seconds per day.
There no CPU inside. It's just logic gates and counters, making clever use of an 4.320 MHz OCXO. In case you are wondering why:
24h x 60m x 60s x 50 = 4.320.000
I will be doing  teardown and restore thread that i'll link in later.

Edit:
https://www.eevblog.com/forum/testgear/teardown-and-restauration-of-a-citizen-cqt-101-c-quartz-tester/
(Attachment Link)
(Attachment Link)

Never even knew this existed and now 30 seconds later I'm looking for one on ebay... Want.

Were there other companies who made such magic?

McBryce.

[AVGresponding]

Hello, my name is BreakingOhmsLaw and i suffer from GAS.
Today if have something for you, that probably is new even to this forum.

I present to you *drumroll* the Citizen CQT-101-C Quartz tester.
What is it? Well, basically its a frequency counter for wrist watches. It comes with a little pedestal for you to place a wrist watch on. Theres a hypersensitive microphone inside that listens for the watch ticking.
The ticks are measured with high precision, and the device shows the deviation of the watch in seconds per day.
There no CPU inside. It's just logic gates and counters, making clever use of an 4.320 MHz OCXO. In case you are wondering why:
24h x 60m x 60s x 50 = 4.320.000
I will be doing  teardown and restore thread that i'll link in later.

Edit:
https://www.eevblog.com/forum/testgear/teardown-and-restauration-of-a-citizen-cqt-101-c-quartz-tester/
(Attachment Link)
(Attachment Link)

Welcome to Test Equipment Anonymous, aka The Enablers Association. Expect an acceleration of your symptoms!

That's an intriguing piece of gear, the stated measurement range had me raising an eyebrow, since if a watch is out by 399 seconds a day, I'm not sure what you could do about it.
Surely any trimmer adjustment can't have that big an effect!   

Oh, and SOMEONE here introduced me to Crabbies Alcoholic Ginger Beer. I don't know who you are, but I will find you, and I will breathe ketones on you!   

Well I introduced you to The Ginger Grizzly, not Crabbies Ginger Beer, don't tell me that you went and brought some Crabbies then  , They are like chalk and cheese 

I'll get around to that eventually I expect, but Crabbies is sold by Sainsbury's so it's easy just to add it to my weekly delivery.


EDIT: @bd139, didn't you get a UT210 the other week? There's a thread in Test Equipment where someone is having problems with theirs, thought you might have an insight.

[Specmaster]

Oh, and SOMEONE here introduced me to Crabbies Alcoholic Ginger Beer. I don't know who you are, but I will find you, and I will breathe ketones on you!   

Well I introduced you to The Ginger Grizzly, not Crabbies Ginger Beer, don't tell me that you went and brought some Crabbies then  , They are like chalk and cheese 

I'll get around to that eventually I expect, but Crabbies is sold by Sainsbury's so it's easy just to add it to my weekly delivery.


EDIT: @bd139, didn't you get a UT210 the other week? There's a thread in Test Equipment where someone is having problems with theirs, thought you might have an insight.

Oh! Yeah? Good luck with getting your hands on some Ginger Grizzly, it was part of the Lidl Beer Festival which is now over and when I was there yesterday with the intention of getting more, it was all gone. You clearly are not a regular to Lidl's then, when they get these special items in, they are only on offer for a few days and once the limited stock has gone, its gone until the next festival, next year but not guaranteed  that they will offer the same offerings.


I also have a UT210E along with simply loads of other members here and doing a quick search it seems that it's quite common but Fungus has already posted a link to Joe Smith's YT channel on how he solved the issue.

[AVGresponding]

I don't use Lidl at all; it would be horribly inconvenient for one thing. The Big Smoke probably has many branches, but The Big Rain has few.

I found another Thandar baby scope to get overbid on...   

Here's one for los americanos to have a nosy at, I'd have a bid myself if it weren't for ridiculously complicated and expensive shipping issues between there and here:  https://www.ebay.co.uk/itm/C167871-Lot-3-HP-Triple-Output-DC-Power-Supply-6236A-6236B-6V-2-5A-20V-0-5A/333593869571

[Specmaster]

Today might turn out to be a good day in the specmaster household then, postman has just been and YAH, I now have my MAX134. Funny that though, I had already checked the tracking and it was still showing as being at the Inward MC and would soon sent be to my local delivery office, 

Anyway, I have inspected it with in the antistatic tube that it was packed and it seems to be brand new despite the description stating its USED. Maybe its a customs defeating statement, who knows?

Now to find out if its the solution I need, but first I need to go and prepare the BBQ for another one this evening. Already had more BBQ's this month than I had all last year 

[Specmaster]

I don't use Lidl at all; it would be horribly inconvenient for one thing. The Big Smoke probably has many branches, but The Big Rain has few.

I found another Thandar baby scope to get overbid on...   

Here's one for los americanos to have a nosy at, I'd have a bid myself if it weren't for ridiculously complicated and expensive shipping issues between there and here:  https://www.ebay.co.uk/itm/C167871-Lot-3-HP-Triple-Output-DC-Power-Supply-6236A-6236B-6V-2-5A-20V-0-5A/333593869571

Big Rain  , I'm in the same position as you, Chelmsford and Halifax both cities only have a single store each. The Big Smoke, refers to London, I guess? well yes, they do have more but not as many as people would expect.

I can't find this Thandar baby scope to which you make reference, not that I'd won't to compete with you on it, I already a couple of small form scopes, 1 DSO and 1 analogue, no room for more 

[tggzzz]

Today's "couldn't resist it" acquisition: Keysight 34138A probes.

Standard nice silicone probes, plus two sizes of grippers and a rather fine (in both senses) insulated spear. The exposed part of that is only 3mm long, and it is pleasingly sharp. Not bad for £15 delivered.

[SilverSolder]

Today's "couldn't resist it" acquisition: Keysight 34138A probes.

Standard nice silicone probes, plus two sizes of grippers and a rather fine (in both senses) insulated spear. The exposed part of that is only 3mm long, and it is pleasingly sharp. Not bad for £15 delivered.

I like the retractable sheath idea - so you can plug the probes into equipment that uses "normal" banana posts - is that right?

[bd139]

I don't use Lidl at all; it would be horribly inconvenient for one thing. The Big Smoke probably has many branches, but The Big Rain has few.

I found another Thandar baby scope to get overbid on...   

Here's one for los americanos to have a nosy at, I'd have a bid myself if it weren't for ridiculously complicated and expensive shipping issues between there and here:  https://www.ebay.co.uk/itm/C167871-Lot-3-HP-Triple-Output-DC-Power-Supply-6236A-6236B-6V-2-5A-20V-0-5A/333593869571

There's a couple of 6236B's on UK ebay. You might have to fight me for one though 

[AVGresponding]

Nah, I'm not a big fan of wobbly pointy readouts.

I only liked the low price of a batch of 3 (assuming no-one bids it up ofc).

Today's "couldn't resist it" acquisition: Keysight 34138A probes.

Standard nice silicone probes, plus two sizes of grippers and a rather fine (in both senses) insulated spear. The exposed part of that is only 3mm long, and it is pleasingly sharp. Not bad for £15 delivered.

Nice, even better value than the Pomona ones. Where from?

[GreyWoolfe]

Oh, and SOMEONE here introduced me to Crabbies Alcoholic Ginger Beer. I don't know who you are, but I will find you, and I will breathe ketones on you!   

Alcoholic ginger beer sounds interesting.  I like ginger beer on its own or in Moscow Mules.  On the topic of booze, a friend of Mrs GreyWoolfe has a husband who makes flavored moonshine.  At work she received a quart each of root beer and apple pie shine as a gift.  She tried to pay husband but he said that wife would kill him if he took it, he was originally asking $30 USD a quart which Mrs GreyWoolfe was happy to pay as she got a teaser last week, a wee pint of the root beer that she fell in love with( I enjoyed it also).  The root beer could be stronger but the apple pie shine really does taste like apple pie, just with a good kick in the balls if you drink it too fast.  Served over ice per recommendation, it is a nice sipping beverage.

[tggzzz]

I like the retractable sheath idea - so you can plug the probes into equipment that uses "normal" banana posts - is that right?

These aren't retractable, so they won't fit my big bench equipment. For such equipment I generally prefer stackable bananas.

Nice, even better value than the Pomona ones. Where from?

Fleabay one off. Notice them, think 15s, buy them

[mnementh]

      

   You can't even tell that there's ringing with either sample. What all you've done here is to prove that a 40-year-old scope still has value. 

mnem
 

That Siglent only has a 50MHz B/W. I would cut it SOME slack.

I wouldn't 

Why not? Just cuz it's med...? 

In all honesty... that signal on med's 2465 is a gorgeous example. Brings a tear to my eye; knowing this generation will never know the joy of actually SEEING the signal, even through a "microscope lens", as opposed to seeing a transcript of what a computer subroutine THINKS it sees and extrapolates from datapoints.

mnem
 

Turn off interpolation, and look at the unconnected dots. Then you can see what you can't see.

Being able to figure out what you can't see is not the same as being able to see it. Those dots are the same kind of lie as the statistics on any kind of chart used by any politician to sell whatever big lie they're pushing at the moment.

In what way are they a lie? You may misinterpret them, but that is a different problem.

The lie is the one you tell yourself when you say that those dots are an accurate representation. What they are is the equivalent of driving down the highway at speed with your eyes closed, and blinking them open at periodic intervals.

Neither is an analogue trace reality; it is only an approximation thereof. Start by considering the effects of the probes on the circuit, then move onto frequency and (especially) phase distortions.

(Geocities font omitted for legibility )

That distortion is the "microscope lens" I referred to earlier. The difference is now you're COMPOUNDING that same exact distortion by the above described "driving down the highway and blinking", etc scenario. Then, to make it even more fun, we feed those periodic single frames into a computer morph program, and call what it spits out "reality". In essence, it's stop-motion photography.

In other words: DSO is like Claymation; Analog is like looking at the world through a camera lens.

mnem
Geocities font reinstated out of sheer perversity.

[Kosmic]

Got 2 ebay sellers from asia canceling my order recently saying they can't ship to Canada anymore due to the current situation It's true that they are particularly slow these days.

If I can't get parts to fix and/or build anything, it's going to get really boring around here 

[mnementh]

   Today's "couldn't resist it" acquisition: Keysight 34138A probes.

Standard nice silicone probes, plus two sizes of grippers and a rather fine (in both senses) insulated spear. The exposed part of that is only 3mm long, and it is pleasingly sharp. Not bad for £15 delivered.

I like the retractable sheath idea - so you can plug the probes into equipment that uses "normal" banana posts - is that right?

@SilverSolder: I think those are not retractable, but rather just the usual cheap vinyl caps that come on both ends of all probe leads nowadays.

@tggzzz: Did you get the full set above for that price, or was it missing the (+) spear and grabbit? I've shopped that set before; it's still a reasonable value at the regular price of ~US$30 from Newark, et al.

mnem

[tggzzz]

In other words: DSO is like Claymation; Analog is like looking at the world through a camera lens.
Geocities font reinstated out of sheer perversity.

Just as well that movies are "analogue" and not "digitised" at Xfps. Shame the anti-aliasing filter technology is deficient.

(Geocities abortion deleted for simplicity)

[tggzzz]

@tggzzz: Did you get the full set above for that price, or was it missing the (+) spear and grabbit? I've shopped that set before; it's still a reasonable value at the regular price of ~US$30 from Newark, et al.

The bag was still sealed, and I had to cut it to get at the probes. Even then opening the ziplock was a bit of a pain. Couldn't be better

Your picture is what I received, down to the two black and one red grabbers. Yes, it seemed like sufficiently good value that I offered £12 against his £13.50 asking price.

[mnementh]

You're almost as unrepentant a cheap-arse as I am. 

Yes, you should notice I DID say analog was like "looking at the world through a camera lens", not the simpler analogy of Claymation vs Live Cinematography. There is a huge but subtle difference; both in the nature of what is seen and how it can be preserved for posterity. I DO remember the nightmare of trying to capture waveforms on a 2465 with that blasted Polaroid contraption.

mnem
};=)~~~~<

[drussell]

Alcoholic ginger beer sounds interesting.

Indeed.  I make simple ginger ale all the time but have never tried fermenting longer than about 2-3 days, basically just enough to make it carbonated for more of a soda-pop style ginger ale.   I've been thinking of trying it much longer, though not all the way to dryness...  I don't think Nicole started another batch of wine yet so I think we have a spare fermenter, carboy and trap and stuff right now....

I should try it just to see what happens even though I have no idea what I'm doing, just make it up as I go. 

I've never even checked with a hydrometer to see if it's even mildly alcoholic after the couple days I usually do for the regular ginger ale.

[Specmaster]

4503 Update time.
Plugged in the replacement MAX134 and...... it just displays "OR" on each and every range, either it was duff one that I purchased or it has zapped with static despite it being packed in an anti-static tube. Removed and plugged back the old one and everything is back to where it was before, so I'm no further forward with this 

I have opened a dispute with the seller via eBay 

[tggzzz]

I DO remember the nightmare of trying to capture waveforms on a 2465 with that blasted Polaroid contraption.

Ditto, 465 and 7000 series in my case.

I also remember the "joys" of analogue storage scopes, and why digitising scopes were jumped on. Remembering that, I recently flogged an imperfect but working 464 for £40 more than I paid for it

I also remember the crap limitations of even high-end digitising scopes before this milennium, and why people held onto their analogue scopes.

[0culus]

I rather enjoy my HP 1727A. The storage is fairly useless, but variable persistence is excellent for working with low frequency signals when you need the timebase turned way down.